Hotbox detector for railway cars and the like



Nov. 25, 1952 D, KEMPF 2,619,586

HOTBOX DETECTOR FOR RAILWAY CARS AND THE LIKE Filed MaICh 13, 1950 2 SHEETS-SHEET l Ez'yj X Y I [725672/07 260722 M fly 7zb4/flf/zaym NOV. 25, 1952 KEMPF 2,619,586

HOTBOX DETECTOR FOR RAILWAY CARS AND THE LIKE fwefzk?" fieazz R. Aew/ Patented Nov. 25, 1952 HOTBOX DETECTOR FOR RAIL'WAY CAR AND THE LIKE Dean R. Kempf, Minneapolis, Minn., assignor of fifty per cent to Aubrey V. Casey, Red Wing,

Minn.

Application March 13, 1950, Serial No. 149,290 7 3 Claims. 1

My invention relates generally to journals on railway cars, and more specifically, to means for detecting overheated journal bearings in the trucks of railway cars.

Despite care exercised in the maintenance of proper lubrication and bearing conditions in journal boxes, a journal bearing sometimes fails to obtain proper lubrication and overheats, resulting in a so-colled hot box. The heat becomes sufiicient to cause the oil-saturated cotton waste in the journal box to ignite, thus creating further heat, which, if not detected and checked, results in a broken bearing and, in some instances, the wrecking of an entire train. The primary object of my invention is the provision of means responsive to the heating of a journal bearing to a pre-determined temperature for automatically causing the brakes of the railway cars to be set to stop the train.

Another object of my invention is the provision of a valve in the pneumatic brake system of a railway car, which is controlled by means responsive to heating of a journal bearing to a predetermined temperature to operate said brake system.

Another object of my invention is the provision of means whereby the above-mentioned valve can be reset to operate upon reoccurrence of a hot box or overheated condition of the journal box. A still further object of my invention is the provision of a valve having an operating link therefor extending into the journal bearing and secured thereto by anchoring means having a lower melting temperature than that of the journal bearing, whereby overheating of said journal bearing will cause the anchoring means to melt and permit the valve to open and operate the brake system.

Another object of my invention is the provision of hot box detecting and brake-operating mechanism as set forth, which is relatively inexpensive to build and install in a journal box and which is eflicient in operation and durable in use.

The above and still further objects and advantages of my invention will become apparent from the following detailed specification, appended claims, and attached drawings.

Referring to the drawings, wherein like characters indicate like parts throughout the several views:

Fig. 1 is a fragmentary view in side elevation of a railway car, showing my novel device attached to the journal boxes of one of the trucks thereof;

Fig. 2 is a fragmentary section on an enlarged scale, taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a still further enlarged detail, partly in elevation and partly in section, taken substantially on the line 3-3 of Fig. 2;

Fig. 4 is an enlarged transverse section taken on the line 4-4 of Fig. 3; and

Fig. 5 is a view corresponding to Fig. 3 but showing a modified form of the invention.

Referring with greater particularity to the preferred embodiment of the invention illustrated in Figs. 1-3 inclusive, the numeral l indicates a railway car supported by wheels 2 mounted in journal boxes 3 of a conventional truck 4. The Wheels 2 are mounted on axles 5, one of which is shown, which, at their opposite ends, are provided with trunnions 6 that are contained one each within a journal box 3. Each of the journal bearings 1 is secured within each of the journal boxes 3 and rests upon a trunnion 6 contained therein, whereby to bear the Weight of the truck 4 associated therewith and the car I. Each of the journal bearings I is further provided with a babbitted bearing face 8 and is securely locked within the journal box 3 in any suitable manner.

As shown in Fig. 2, the bottom of the journal box 3 is packed with cotton waste X saturated with oil, whereby lubrication is supplied to the trunnion 6. As sometimes occurs, and as above indicated, the cotton waste X becomes sufficiently dry so as to prevent proper lubrication between the trunnion 6 and the metal of the bearing face 8. Inasmuch as the load between the trunnion 6 and the bearing 1 is very great, improper lubrication of the trunnion 6 causes the temperature due to friction between the trunnion 6 and the metal of the bearing face 8 to rise very rapidly to a point where the cotton waste X ignites, thus further aggravating the heat condition within the journal'box 3. For the purpose of detecting an overheated condition in a given journal box 3 and for causing the air brake system of the railway car to function, whereby to stop the train, I provide an air valve 9, which is adapted to be connected by fluid pressure conduit means such as pipes [0, to the air brake system not shown, but which is of the conventional type wherein air under pressure in a brake-operating cylinder is released to cause the brakes to operate. Each of the valves 9 comprises a valve body ll, having an opening l2 therein leading to atmosphere, and a valve plug [3 seated in the valve body H. The valve plug I3 is preferably made from brass or the like and, when properly seated in the valve body ll, has sealing engagement therewith. As shown, the plug I3 is provided with an axially-extended central passage l4, through which loosely extends a rigid link 15, threaded at its upper end to receive a wing nut 16 which bears against the top of the valve plug 13. As shown, the valves 9 are one each rigidly mounted on the truck 4 in spaced relationship to its respective journal box 3, the lower end portion of the link 7 l extending downwardly through an opening H in the journal box 3 and into a recess I8 in the bearing 1 aligned with the opening II. The lower end of the link I5 is anchored in the recess I8 by a fusible anchoring plug l9 which has threaded engagement with the lower end of the link I5 and which is fused to the metal of the bearing I. The fusible anchoring, plug I9 may be any one of a number of metallic elements or alloys which have a lower melting point than he babbitted face 8 of the bearing I.

Intermediate each journal box 3 and its respective valve 9, the link I5 thereof is provided with a circumferentially-extended groove which receives a laterally-projecting flange in the nature of a split washer or clip 21 which provides a base of reaction for one end Qf 'a coil compression spring 22 interposed therebetween and the top of the journal box 3, and loosely encompassing the link |5. A cotter pin or the like 23 extends transversely through the link I5 intermediate the washer 2| and the valve plug; l3 and provides a removable. abutment engageable with the valve plug I3 when the link I5 is rendered operative. It will be noted that the spring 22 is in a compressed state when the lower end of the link |5' is anchored in the bearing I by the fusible plug I9 and exerts a yielding bias upon the washer 2| and the link I5 in the direction of the valve plug l3.

If for any reason, the trunnion 6 is not properly lubricated, heat generated in the bearing 1- will be quickly transferred to the anchoring plug l9 until the plug; I9 is caused to melt. At this point, bias of the spring 22 against the washerv 2| will raise the link l5 and the cotter pin 23 to bring the pin 23. into engagement with the valve plug I3. The impact between the cotter pin 23 and the valve plug I3 will be sufiicient to unseat the plug I3 from the valve body II, the same being raised to a point where the washer 2| engages the bottom of the valve body Unseating of the valve plug I3 will of course permit air under pressure to escape from the brake cylinder through the conduit l9 and outwardly from the outlet |2 of the valve 9, causing the brake mechanism to stop the. train.

After the train has stopped and the hot box has been located and remedied, the cotter pin 23 is removed from. the link I5 and the wing nut I6 screwed downwardly on the link I5 until the valve plug I3 is properly seated in the valve body II, the washer 2| engaging the bottom of the valve body II. The train may then proceed to operate until brought to a suitable point for servicing at which a new anchoring plug |9 may be applied tothe journal box. From the above it should be obvious that the re -closing of the valve 9 consumes but a minimum of time and eifort and, once the journal box isagainproperly lubricated, operation of the train may be resumed.

With, reference to the modified form of the invention shown in Fig. 5, the. journal box, wheel bearing, babbitted bearing face thereof, and the air pressure conduit or pipe, are all identical to the corresponding parts shown in Figs. 1-3 inclusive and carry the same numerals with prime marks added. However, in this form of the invention, the fusible anchoring plug I9 seated in the recess I8 is secured to the lower end of a stem 24 which projects upwardly through the opening H in the journal box 3' in an eye 25. A flexible cable 26 has its lower end secured in one end of the conduit I0.

4 the, eye and its upper end rigidly secured through an eye; 2] in a stem 28 which extends loosely through a substantially semispherical valve element 29 seated in a valve body 30 at A nut or burr 3| screw-threaded onto the upper end of the stem 28 maintains the valve element 29 in tight sealing engagement with the valve 30.

The operation of the device of Fig. 5 is similar to that of the device of Figs. 1-4 inclusive, with the exception that the valve element 29 is biased away from seating engagement with the valve body 30 by the pressure of air within the valve body 30 and the conduit; I0. Suflicient heat generated in the bearing I will melt the valve plug l9 and release the stem 24 whereby to permit unseating movement of the, valveelement 29 and subsequent escape of air through the valve 30, causing the brakes to beset. Engagement of the eye 21 with the bottom of the valve body 30 limits unseating movement of the valve plug 29 and prevents loss thereof. The valve plug 29 may be reseated in the valve 39 in substantially the same manner as the valve plug l3 in the valve 9, the eye 21 engaging the body of the valve 30 and the, nut 3| screwed downwardly on the stem 23. The arrangements above described have been referred to, as being operative to set the brakes ofthe railway car or train. It should be obvious however that the same is applicable to a warning signal whereby a train operator may be made aware of a hot box and cause the brakes to be manipulated in the usual manner.

My invention has been thoroughly tested and found to be completely satisfactory for the ac,- complishment of the, objectives set forth; and, while I have shown and described a preferred embodiment and a single modification of my improved device, it will be understood that they same is capable of further modification without. departure from the spirit and scope of they invene tion, as defined in the appended claims.

What I claim is:

1. The combination with a railway car including a journal box having a bearing therein, and an air brake system, of a valve body in said air brake system, an opening through said body defining a conical valve seat, a valve plug enga eable with said valve seat whereby to prevent passage of air through said valve, a. link extending loosely axially through said valve plug and having a screw-threaded end projecting outwardly from one end thereof, nut means on said screwthreaded end engageable with the large end of said valve plug, the opposite end of said link projecting through an opening in said journal box, said bearing being provided with a recess aligned with the opening in said journal box, a fusible anchoring plug in said recess, said anchoring plug having a lower melting point than said bearing, a detachable abutment on said link of a size permitting passage thereof through the opening defining said valve seat, said abutment being normally spaced from the reduced. end of said valve seat and engageable therewithupon longitudinal movements of said link, a flange on said link intermediate said abutment and said journal box, said flange having a transverse width greater than the reduced opening defining said conical valve seat, and a coil compression spring encompassing said link and biasing same and said abutment in a direction to unseat said valve plug upon fusing of said anchoring plug, said flange being spaced from the threaded portion of the outer end of said link a-distance less than the thickness of said valve plug, whereby when said detachable abutment has been removed from said link, said valve plug may be manually reseated by adjustment of said nut means.

2. The structure defined in claim 1 in which said flange is in the nature of a split washer removably received within a circumferentiallyextended groove in said link and in which said coil spring is interposed between said flange and said journal box.

3. The combination with a railway car including a journal box assembly having a bearing therein, and an air brake system, of a valve body in said air brake system, a valve seat in said body, a valve plug engageable with said valve seat whereby to prevent passage of air through said valve, a link extending loosely axially through said valve plug and having a screwthreaded end projecting outwardly thereof, nut means on said screw-threaded end engageable with the adjacent end of said valve plug, the opposite end of said link projecting through an opening in the journal box, said bearing being provided with a recess, a fusible anchoring plug in said recess, said anchoring plug having a [lower melting point than said bearing, the oppo- ;'site end of said link being operatively anchored to said anchoring plug, means yieldingly biasing said valve plug toward a position to unseat same, and an enlarged portion on said link incapable of passing through said opening in said journal box, said enlargement being spaced from the threaded portion of said link a distance less than the thickness of said valve plug whereby said valve plug may be manually reseated by adjustment of said nut means.

DEAN R. KEMPF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,058,993 Marvin Apr. 15, 1913 1,270,954 Jordan et a1. July 2, 1918 

